Feldman Michael J, Verbeek P Richard, Lyons David G, Chad Sandra J, Craig Alan M, Schwartz Brian
Sunnybrook-Osler Center for Prehospital Care, 10 Carlson Court, Suite 640, Toronto, Ontario, Canada.
Acad Emerg Med. 2006 Sep;13(9):954-60. doi: 10.1197/j.aem.2006.04.018. Epub 2006 Aug 7.
Although the Medical Priority Dispatch System (MPDS) is widely used by emergency medical services (EMS) dispatchers to determine dispatch priority, there is little evidence that it reflects patient acuity. The Canadian Triage and Acuity Scale (CTAS) is a standard patient acuity scale widely used by Canadian emergency departments and EMS systems to prioritize patient care requirements.
To determine the relationship between MPDS dispatch priority and out-of-hospital CTAS.
All emergency calls on a large urban EMS communications database for a one-year period were obtained. Duplicate calls, nonemergency transfers, and canceled calls were excluded. Sensitivity and specificity to detect high-acuity illness, as well as positive predictive value (PPV) and negative predictive value (NPV), were calculated for all protocols.
Of 197,882 calls, 102,582 met inclusion criteria. The overall sensitivity of MPDS was 68.2% (95% confidence interval [CI] = 67.8% to 68.5%), with a specificity of 66.2% (95% CI = 65.7% to 66.7%). The most sensitive protocol for detecting high acuity of illness was the breathing-problem protocol, with a sensitivity of 100.0% (95% CI = 99.9% to 100.0%), whereas the most specific protocol was the one for psychiatric problems, with a specificity of 98.1% (95% CI = 97.5% to 98.7%). The cardiac-arrest protocol had the highest PPV (92.6%, 95% CI = 90.3% to 94.3%), whereas the convulsions protocol had the highest NPV (85.9%, 95% CI = 84.5% to 87.2%). The best-performing protocol overall was the cardiac-arrest protocol, and the protocol with the overall poorest performance was the one for unknown problems. Sixteen of the 32 protocols performed no better than chance alone at identifying high-acuity patients.
The Medical Priority Dispatch System exhibits at least moderate sensitivity and specificity for detecting high acuity of illness or injury. This performance analysis may be used to identify target protocols for future improvements.
尽管医疗优先调度系统（MPDS）被紧急医疗服务（EMS）调度员广泛用于确定调度优先级，但几乎没有证据表明它能反映患者的病情严重程度。加拿大分诊与 acuity 量表（CTAS）是一种标准的患者病情严重程度量表，被加拿大急诊科和 EMS 系统广泛用于确定患者护理需求的优先级。
确定 MPDS 调度优先级与院外 CTAS 之间的关系。
获取了一个大型城市 EMS 通信数据库中为期一年的所有紧急呼叫记录。排除重复呼叫、非紧急转运和取消的呼叫。计算所有协议检测高病情严重程度疾病的敏感性和特异性，以及阳性预测值（PPV）和阴性预测值（NPV）。
在 197,882 次呼叫中，102,582 次符合纳入标准。MPDS 的总体敏感性为 68.2%（95%置信区间[CI]=67.8%至 68.5%），特异性为 66.2%（95%CI=65.7%至 66.7%）。检测高病情严重程度疾病最敏感的协议是呼吸问题协议，敏感性为 100.0%（95%CI=99.9%至 100.0%），而最特异的协议是精神问题协议，特异性为 98.1%（95%CI=97.5%至 98.7%）。心脏骤停协议的 PPV 最高（92.6%，95%CI=90.3%至 94.3%），而抽搐协议的 NPV 最高（85.9%，95%CI=84.5%至 87.2%）。总体表现最佳的协议是心脏骤停协议，总体表现最差的协议是未知问题协议。32 个协议中有 16 个在识别高病情严重程度患者方面的表现并不比随机情况更好。
医疗优先调度系统在检测高病情严重程度的疾病或损伤方面表现出至少中等的敏感性和特异性。这种性能分析可用于确定未来改进的目标协议。
